Bailout Intracranial Angioplasty or Stenting After Thrombectomy for Acute Large Vessel Occlusion: 1-Year Outcomes of ANGEL-REBOOT

BACKGROUND: The long-term benefits of bailout intracranial angioplasty or stenting (BAOS) after thrombectomy in patients with acute large vessel occlusion remain unclear. This study compared BAOS with standard therapy in patients with large vessel occlusion with unsuccessful recanalization (expanded Thrombolysis In Cerebral Infarction score 0–2a) or >70% residual stenosis after thrombectomy. METHODS: ANGEL-REBOOT (Randomized Study of Bailout Intracranial Angioplasty Following Thrombectomy for Acute Large Vessel Occlusion) was a multicenter, open-label, blinded–end point, randomized trial conducted across 36 Chinese hospitals. Patients ≥18 years of age with anterior or posterior circulation large vessel occlusion within 24 hours of stroke onset were enrolled. After identification of thrombectomy failure or high-grade residual stenosis, patients were randomly assigned to the BAOS group (intervention) or the standard therapy group (control), in which thrombectomy was continued or terminated. The use of tirofiban was permitted in both groups during and after the procedure. In the intention-to-treat population, the primary outcome was analyzed using an assumption-free ordinal analysis (Wilcoxon-Mann-Whitney test) to compare the modified Rankin Scale scores (ordinal variable ranging from 0 to 6) between groups at 1-year follow-up, from which the generalized odds ratio was derived. Secondary outcomes included stroke recurrence in the treated artery and all-cause mortality within 1 year, analyzed using Cox proportional hazards models. RESULTS: A total of 348 patients were randomly assigned (176 to the BAOS group and 172 to the standard therapy group) and followed for 90 days, from December 19, 2021, to June 2, 2023. Of these, 326 patients (166 in the BAOS group and 160 in the standard therapy group) completed the 1-year follow-up. Compared with standard therapy, BAOS significantly improved the 1-year modified Rankin Scale score distribution (generalized odds ratio, 1.34 [95% CI, 1.05–1.73]; P =0.02). Fewer stroke recurrences in the treated artery occurred in the BAOS group than in the standard therapy group (7 of 166 [4%] versus 21 of 160 [13%]; hazard ratio, 0.30 [95% CI, 0.13–0.71]; P =0.006). One-year mortality rates were similar between groups (25 of 166 [15%] versus 27 of 160 [17%]; hazard ratio, 0.87 [95% CI, 0.50–1.50]). CONCLUSIONS: Among Chinese patients with large vessel occlusion with unsuccessful recanalization or high-grade residual stenosis after thrombectomy, BAOS was associated with reduced disability and stroke recurrence after 1 year compared with standard therapy. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT05122286.